Powerbook will not start

Are you talking about a MacBook? That is what this forum is for. If you really have a PowerBook you'll want to post your question here.

If on the other hand you have a MacBook, can you give us some more details? Like does anything happen when you press the power button? If so, describe what goes on on the screen. If not, have you tried resetting the System Management Controller?

Best of luck.